/**
 
 @Name：layui.dropdown 下拉菜单组件
 @License：MIT

 */

layui.define(['jquery', 'laytpl', 'lay'], function (exports) {
  //"use strict";

  var $ = layui.$
    , laytpl = layui.laytpl
    , hint = layui.hint()
    , device = layui.device()
    , clickOrMousedown = (device.mobile ? 'click' : 'mousedown')

    //模块名
    , MOD_NAME = 'dropdown'
    , MOD_INDEX = 'layui_' + MOD_NAME + '_index' //模块索引名

    //外部接口
    , dropdown = {
      config: {}
      , index: layui[MOD_NAME] ? (layui[MOD_NAME].index + 10000) : 0

      //设置全局项
      , set: function (options) {
        var that = this;
        that.config = $.extend({}, that.config, options);
        return that;
      }

      //事件
      , on: function (events, callback) {
        return layui.onevent.call(this, MOD_NAME, events, callback);
      }
    }

    //操作当前实例
    , thisModule = function () {
      var that = this
        , options = that.config
        , id = options.id;

      thisModule.that[id] = that; //记录当前实例对象

      return {
        config: options
        //重置实例
        , reload: function (options) {
          that.reload.call(that, options);
        }, destroy() {
          delete thisModule.that[id];
        }
      }
    }

    //字符常量
    , STR_ELEM = 'layui-dropdown', STR_HIDE = 'layui-hide', STR_DISABLED = 'layui-disabled', STR_NONE = 'layui-none'
    , STR_ITEM_UP = 'layui-menu-item-up', STR_ITEM_DOWN = 'layui-menu-item-down', STR_MENU_TITLE = 'layui-menu-body-title', STR_ITEM_GROUP = 'layui-menu-item-group', STR_ITEM_PARENT = 'layui-menu-item-parent', STR_ITEM_DIV = 'layui-menu-item-divider', STR_ITEM_CHECKED = 'layui-menu-item-checked', STR_ITEM_CHECKED2 = 'layui-menu-item-checked2', STR_MENU_PANEL = 'layui-menu-body-panel', STR_MENU_PANEL_L = 'layui-menu-body-panel-left'

    , STR_GROUP_TITLE = '.' + STR_ITEM_GROUP + '>.' + STR_MENU_TITLE

    //构造器
    , Class = function (options) {
      var that = this;
      that.index = ++dropdown.index;
      that.config = $.extend({}, that.config, dropdown.config, options);
      that.init();
    };

  //默认配置
  Class.prototype.config = {
    trigger: 'click' //事件类型
    , content: '' //自定义菜单内容
    , className: '' //自定义样式类名
    , style: '' //设置面板 style 属性
    , show: false //是否初始即显示菜单面板
    , isAllowSpread: true //是否允许菜单组展开收缩
    , isSpreadItem: true //是否初始展开子菜单
    , data: [] //菜单数据结构
    , delay: 300 //延迟关闭的毫秒数，若 trigger 为 hover 时才生效
  };

  //重载实例
  Class.prototype.reload = function (options) {
    var that = this;
    that.config = $.extend({}, that.config, options);
    that.init(true);
  };

  //初始化准备
  Class.prototype.init = function (rerender) {
    var that = this
      , options = that.config
      , elem = options.elem = $(options.elem);

    //若 elem 非唯一
    if (elem.length > 1) {
      layui.each(elem, function () {
        dropdown.render($.extend({}, options, {
          elem: this
        }));
      });
      return that;
    }

    //若重复执行 render，则视为 reload 处理
    if (!rerender && elem[0] && elem.data(MOD_INDEX)) {
      ;
      var newThat = thisModule.getThis(elem.data(MOD_INDEX));
      if (!newThat) return;

      return newThat.reload(options);
    };

    //初始化 id 参数
    options.id = ('id' in options) ? options.id : that.index;

    if (options.show) that.render(rerender); //初始即显示
    that.events(); //事件
  };

  //渲染
  Class.prototype.render = function (rerender) {
    var jueDropdown = $('#layui-dropdown-ue');
    if (jueDropdown.size() == 0) {
      jueDropdown = $('<div id="layui-dropdown-ue" class="layui-uieditor"></div>');
      $('body').append(jueDropdown);
    }
    var that = this
      , options = that.config
      , elemBody = jueDropdown//$('body')

      //默认菜单内容
      , getDefaultView = function () {
        var elemUl = $('<ul class="layui-menu layui-dropdown-menu"></ul>');
        var data = typeof options.data == 'function' && options.data(that.e) || options.data || [];
        if (data.length > 0) {
          eachItemView(elemUl, data)
        } else {
          elemUl.html('<li class="layui-menu-item-none">no menu</li>');
        }
        return elemUl;
      }

      //遍历菜单项
      , eachItemView = function (views, data) {
        //var views = [];
        layui.each(data, function (index, item) {
          //是否存在子级
          var isChild = item.child && item.child.length > 0
            , isSpreadItem = ('isSpreadItem' in item) ? item.isSpreadItem : options.isSpreadItem
            , title = item.templet
              ? laytpl(item.templet).render(item)
              : (options.templet ? laytpl(options.templet).render(item) : item.title)

            //初始类型
            , type = function () {
              if (isChild) {
                item.type = item.type || 'parent';
              }
              if (item.type) {
                return ({
                  group: 'group'
                  , parent: 'parent'
                  , '-': '-'
                })[item.type] || 'parent';
              }
              return '';
            }();

          if (type !== '-' && (!item.title && !item.id && !isChild)) return;

          //列表元素
          var viewLi = $(['<li' + function () {
            var className = {
              group: 'layui-menu-item-group' + (
                options.isAllowSpread ? (
                  isSpreadItem ? ' layui-menu-item-down' : ' layui-menu-item-up'
                ) : ''
              )
              , parent: STR_ITEM_PARENT
              , '-': 'layui-menu-item-divider'
            };
            if (isChild || type) {
              return ' class="' + className[type] + '"';
            }
            return '';
          }() + '>'

            //标题区
            , function () {
              //是否超文本
              var viewText = ('href' in item) ? (
                '<a href="' + item.href + '" target="' + (item.target || '_self') + '">' + title + '</a>'
              ) : title;

              //是否存在子级
              if (isChild) {

                return '<div class="' + STR_MENU_TITLE + (item.disabled ? ' layui-disabled' : '') + '">' + viewText + function () {
                  if (type === 'parent') {
                    return '<i class="layui-icon layui-icon-right"></i>';
                  } else if (type === 'group' && options.isAllowSpread) {
                    return '<i class="layui-icon layui-icon-' + (isSpreadItem ? 'up' : 'down') + '"></i>';
                  } else {
                    return '';
                  }
                }() + '</div>'

              }
              return '<div class="' + STR_MENU_TITLE + (item.disabled ? ' layui-disabled' : '') + '">' + viewText + '</div>';
            }()
            , '</li>'].join(''));

          viewLi.data('item', item);

          //子级区
          if (isChild) {
            var elemPanel = $('<div class="layui-panel layui-menu-body-panel"></div>')
              , elemUl = $('<ul></ul>');

            if (type === 'parent') {
              elemPanel.append(eachItemView(elemUl, item.child));
              viewLi.append(elemPanel);
            } else {
              viewLi.append(eachItemView(elemUl, item.child));
            }
          }

          views.append(viewLi);
        });
        return views;
      }

      //主模板
      , TPL_MAIN = ['<div class="layui-dropdown layui-border-box layui-panel layui-anim layui-anim-downbit">'
        , '</div>'].join('');

    //如果是右键事件，则每次触发事件时，将允许重新渲染
    if (options.trigger === 'contextmenu' || lay.isTopElem(options.elem[0])) rerender = true;

    //判断是否已经打开了下拉菜单面板
    if (!rerender && options.elem.data(MOD_INDEX + '_opened')) return;

    //记录模板对象
    that.elemView = $(TPL_MAIN);
    that.elemView.append(options.content || getDefaultView());

    //初始化某些属性
    if (options.className) that.elemView.addClass(options.className);
    if (options.style) that.elemView.attr('style', options.style);


    //记录当前执行的实例索引
    dropdown.thisId = options.id;

    //插入视图
    that.remove(); //移除非当前绑定元素的面板
    elemBody.append(that.elemView);
    options.elem.data(MOD_INDEX + '_opened', true);

    //坐标定位
    that.position();
    thisModule.prevElem = that.elemView; //记录当前打开的元素，以便在下次关闭
    thisModule.prevElem.data('prevElem', options.elem); //将当前绑定的元素，记录在打开元素的 data 对象中

    //阻止全局事件
    that.elemView.find('.layui-menu').on(clickOrMousedown, function (e) {
      lay.stope(e);
    });

    //触发菜单列表事件
    that.elemView.find('.layui-menu li').on('click', function (e) {
      var othis = $(this)
        , data = othis.data('item') || {}
        , isChild = data.child && data.child.length > 0;

      if (!isChild && data.type !== '-') {
        that.remove();
        typeof options.click === 'function' && options.click(data, othis);
      }
    });

    //触发菜单组展开收缩
    that.elemView.find(STR_GROUP_TITLE).on('click', function (e) {
      var othis = $(this)
        , elemGroup = othis.parent()
        , data = elemGroup.data('item') || {}

      if (data.type === 'group' && options.isAllowSpread) {
        thisModule.spread(elemGroup);
      }
    });

    //如果是鼠标移入事件，则鼠标移出时自动关闭
    if (options.trigger === 'mouseenter') {
      that.elemView.on('mouseenter', function () {
        clearTimeout(thisModule.timer);
      }).on('mouseleave', function () {
        that.delayRemove();
      });
    }

  };

  //位置定位
  Class.prototype.position = function (obj) {
    var that = this
      , options = that.config;

    lay.position(options.elem[0], that.elemView[0], {
      position: options.position
      , e: that.e
      , clickType: options.trigger === 'contextmenu' ? 'right' : null
    });
  };

  //删除视图
  Class.prototype.remove = function () {
    var that = this
      , options = that.config
      , elemPrev = thisModule.prevElem;

    //若存在已打开的面板元素，则移除
    if (elemPrev) {
      elemPrev.data('prevElem') && (
        elemPrev.data('prevElem').data(MOD_INDEX + '_opened', false)
      );
      elemPrev.remove();
    }
  };

  //延迟删除视图
  Class.prototype.delayRemove = function () {
    var that = this
      , options = that.config;
    clearTimeout(thisModule.timer);

    thisModule.timer = setTimeout(function () {
      that.remove();
    }, options.delay);
  };

  //事件
  Class.prototype.events = function () {
    var that = this
      , options = that.config;

    //如果传入 hover，则解析为 mouseenter
    if (options.trigger === 'hover') options.trigger = 'mouseenter';

    //解除上一个事件
    if (that.prevElem) that.prevElem.off(options.trigger, that.prevElemCallback);

    //记录被绑定的元素及回调
    that.prevElem = options.elem;
    that.prevElemCallback = function (e) {
      if (options.trigger === 'contextmenu') {
        lay.stope(e);
      }
      clearTimeout(thisModule.timer);
      that.e = e;
      that.render();
      e.preventDefault();

      //组件打开完毕的时间
      typeof options.ready === 'function' && options.ready(that.elemView, options.elem, that.e.target);
    };

    //触发元素事件
    options.elem.on(options.trigger, that.prevElemCallback);

    //如果是鼠标移入事件
    if (options.trigger === 'mouseenter') {
      //直行鼠标移出事件
      options.elem.on('mouseleave', function () {
        that.delayRemove();
      });
    }
  };

  //记录所有实例
  thisModule.that = {}; //记录所有实例对象

  //获取当前实例对象
  thisModule.getThis = function (id) {
    var that = thisModule.that[id];
    // if (!that) hint.error(id ? (MOD_NAME + ' instance with ID \'' + id + '\' not found') : 'ID argument required');
    return that;
  };

  //设置菜单组展开和收缩状态
  thisModule.spread = function (othis) {
    //菜单组展开和收缩
    var elemIcon = othis.children('.' + STR_MENU_TITLE).find('.layui-icon');
    if (othis.hasClass(STR_ITEM_UP)) {
      othis.removeClass(STR_ITEM_UP).addClass(STR_ITEM_DOWN);
      elemIcon.removeClass('layui-icon-down').addClass('layui-icon-up');
    } else {
      othis.removeClass(STR_ITEM_DOWN).addClass(STR_ITEM_UP);
      elemIcon.removeClass('layui-icon-up').addClass('layui-icon-down')
    }
  };

  //全局事件
  ; !function () {
    var _WIN = $(window)
      , _DOC = $(document);

    //自适应定位
    _WIN.on('resize', function () {
      if (!dropdown.thisId) return;
      var that = thisModule.getThis(dropdown.thisId);
      if (!that) return;

      if (!that.elemView || !that.elemView[0] || !$('.' + STR_ELEM)[0]) {
        return false;
      }

      var options = that.config;

      if (options.trigger === 'contextmenu') {
        that.remove();
      } else {
        that.position();
      }
    });



    //点击任意处关闭
    _DOC.on(clickOrMousedown, function (e) {
      if (!dropdown.thisId) return;
      var that = thisModule.getThis(dropdown.thisId)
      if (!that) return;

      var options = that.config;

      //如果触发的是绑定的元素，或者属于绑定元素的子元素，则不关闭
      //满足条件：当前绑定的元素不是 body document，或者不是鼠标右键事件
      if (!(lay.isTopElem(options.elem[0]) || options.trigger === 'contextmenu')) {
        if (
          e.target === options.elem[0] ||
          options.elem.find(e.target)[0] ||
          e.target === that.elemView[0] ||
          (that.elemView && that.elemView.find(e.target)[0])
        ) return;
      }

      that.remove();
    });

    //基础菜单的静态元素事件
    var ELEM_LI = '.layui-menu:not(.layui-dropdown-menu) li';
    _DOC.on('click', ELEM_LI, function (e) {
      var othis = $(this)
        , parent = othis.parents('.layui-menu').eq(0)
        , isChild = othis.hasClass(STR_ITEM_GROUP) || othis.hasClass(STR_ITEM_PARENT)
        , filter = parent.attr('lay-filter') || parent.attr('id')
        , options = lay.options(this);

      //非触发元素
      if (othis.hasClass(STR_ITEM_DIV)) return;

      //非菜单组
      if (!isChild) {
        //选中
        parent.find('.' + STR_ITEM_CHECKED).removeClass(STR_ITEM_CHECKED); //清除选中样式
        parent.find('.' + STR_ITEM_CHECKED2).removeClass(STR_ITEM_CHECKED2); //清除父级菜单选中样式
        othis.addClass(STR_ITEM_CHECKED); //添加选中样式
        othis.parents('.' + STR_ITEM_PARENT).addClass(STR_ITEM_CHECKED2); //添加父级菜单选中样式

        //触发事件
        layui.event.call(this, MOD_NAME, 'click(' + filter + ')', options);
      }
    });

    //基础菜单的展开收缩事件
    _DOC.on('click', (ELEM_LI + STR_GROUP_TITLE), function (e) {
      var othis = $(this)
        , elemGroup = othis.parents('.' + STR_ITEM_GROUP + ':eq(0)')
        , options = lay.options(elemGroup[0]);

      if (('isAllowSpread' in options) ? options.isAllowSpread : true) {
        thisModule.spread(elemGroup);
      };
    });

    //判断子级菜单是否超出屏幕
    var ELEM_LI_PAR = '.layui-menu .' + STR_ITEM_PARENT
    _DOC.on('mouseenter', ELEM_LI_PAR, function (e) {
      var othis = $(this)
        , elemPanel = othis.find('.' + STR_MENU_PANEL);

      if (!elemPanel[0]) return;
      var rect = elemPanel[0].getBoundingClientRect();

      //是否超出右侧屏幕
      if (rect.right > _WIN.width()) {
        elemPanel.addClass(STR_MENU_PANEL_L);
        //不允许超出左侧屏幕
        rect = elemPanel[0].getBoundingClientRect();
        if (rect.left < 0) {
          elemPanel.removeClass(STR_MENU_PANEL_L);
        }
      }

      //是否超出底部屏幕
      if (rect.bottom > _WIN.height()) {
        elemPanel.eq(0).css('margin-top', -(rect.bottom - _WIN.height()));
      };
    }).on('mouseleave', ELEM_LI_PAR, function (e) {
      var othis = $(this)
        , elemPanel = othis.children('.' + STR_MENU_PANEL);

      elemPanel.removeClass(STR_MENU_PANEL_L);
      elemPanel.css('margin-top', 0);
    });

  }();

  //重载实例
  dropdown.reload = function (id, options) {
    var that = thisModule.getThis(id);
    if (!that) return this;

    that.reload(options);
    return thisModule.call(that);
  };

  //核心入口
  dropdown.render = function (options) {
    var inst = new Class(options);
    return thisModule.call(inst);
  };

  exports(MOD_NAME, dropdown);
});
